2022-11-15 14:40:39

by Yu Kuai

[permalink] [raw]
Subject: [PATCH v3 02/10] dm: remove free_table_devices

From: Christoph Hellwig <[email protected]>

free_table_devices just warns and frees all table_device structures when
the target removal did not remove them. This should never happen, but
if it did, just freeing the structure without deleting them from the
list or cleaning up the resources would not help at all. So just WARN on
a non-empty list instead.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Yu Kuai <[email protected]>
---
drivers/md/dm.c | 15 +--------------
1 file changed, 1 insertion(+), 14 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 95a1ee3d314e..19d25bf997be 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -833,19 +833,6 @@ void dm_put_table_device(struct mapped_device *md, struct dm_dev *d)
mutex_unlock(&md->table_devices_lock);
}

-static void free_table_devices(struct list_head *devices)
-{
- struct list_head *tmp, *next;
-
- list_for_each_safe(tmp, next, devices) {
- struct table_device *td = list_entry(tmp, struct table_device, list);
-
- DMWARN("dm_destroy: %s still exists with %d references",
- td->dm_dev.name, refcount_read(&td->count));
- kfree(td);
- }
-}
-
/*
* Get the geometry associated with a dm device
*/
@@ -2122,7 +2109,7 @@ static void free_dev(struct mapped_device *md)

cleanup_mapped_device(md);

- free_table_devices(&md->table_devices);
+ WARN_ON_ONCE(!list_empty(&md->table_devices));
dm_stats_cleanup(&md->stats);
free_minor(minor);

--
2.31.1



2022-11-16 22:25:52

by Mike Snitzer

[permalink] [raw]
Subject: Re: [PATCH v3 02/10] dm: remove free_table_devices

On Tue, Nov 15 2022 at 9:10P -0500,
Yu Kuai <[email protected]> wrote:

> From: Christoph Hellwig <[email protected]>
>
> free_table_devices just warns and frees all table_device structures when
> the target removal did not remove them. This should never happen, but
> if it did, just freeing the structure without deleting them from the
> list or cleaning up the resources would not help at all. So just WARN on
> a non-empty list instead.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Signed-off-by: Yu Kuai <[email protected]>

Reviewed-by: Mike Snitzer <[email protected]>